“There were two figures (on the ground) that were then surrounded by police and emergency services, and CPR was being performed.

“One of them has since been taken away in an ambulance and there’s another that still appears to be on the ground on the cobbled steps.

Video Loading

Video Unavailable

Click to playTap to play

The video will start in 8Cancel

Play now

“A helicopter landed and it’s still on the ground and there’s about 24 armed police.

“It’s unclear what’s happening now.

“Journalists and I’m sure everyone else have been told to stay away from the windows. It’s very much a live security situation.

Police close to the Palace of Westminster, London, after sounds similar to gunfire have been heard close to the Palace of Westminster. (Image: PA)

“Things appear to have got a lot calmer now, but traffic has been completely stopped around Parliament Square, which is one of the biggest thoroughfares, so everyone has their TVs on to see what’s actually going on. There are some terrible reports.

“The monitors that are in the corridors which normally tell you what who is speaking, they also give you information about the security level. You kind of get used to seeing that, but this reminds you of what it is like in a situation where there is a severe risk of terrorist attack.”